Question 1

The term mutation refers to

Accepted Answer

A) only changes in the DNA that result in new phenotypes. 
B) only changes in the DNA that result in novel proteins. 
C) any change in the DNA of a cell. 
D) a heritable change in the DNA of a cell. 
E) any change in the cell that changes its survival chances. 
A) only changes in the DNA that result in new phenotypes. 
B) only changes in the DNA that result in novel proteins. 
C) any change in the DNA of a cell. 
D) a heritable change in the DNA of a cell. 
E) any change in the cell that changes its survival chances.

Question 2

Though sickle cell anemia is frequently lethal for individuals who are homozygous for the sickle cell allele, natural selection seems to have maintained that allele in certain geographic locations.A likely explanation for this observation is

Accepted Answer

A) the forward mutation rate to sickle cell is much higher in those regions. 
B) individuals with sickle cell anemia live longer and have more children. 
C) reversion from sickle cell to wild type is prevented in some populations. 
D) individuals who are heterozygous for the sickle cell allele are protected from malaria. 
E) only certain populations have been tested for the presence of the sickle cell allele. 
A) the forward mutation rate to sickle cell is much higher in those regions. 
B) individuals with sickle cell anemia live longer and have more children. 
C) reversion from sickle cell to wild type is prevented in some populations. 
D) individuals who are heterozygous for the sickle cell allele are protected from malaria. 
E) only certain populations have been tested for the presence of the sickle cell allele.

Question 3

Shown below are the results of a series of coinfections using T4 rII- strains similar to those employed by Benzer.Each strain contains a different deletion mutation.Ability to produce wild-type progeny phage is indicated by (+), and (o) indicates no wild-type progeny.     Indicate the order that is most consistent with these data.

Accepted Answer

A) CADBE 
B) ACBDE 
C) BADCE 
D) BEDCA 
E) CEADB 
A) CADBE 
B) ACBDE 
C) BADCE 
D) BEDCA 
E) CEADB

Question 4

The bacterial repair system that corrects mismatched bases after polymerization is able to discriminate between the old and newly made DNA strands because

Accepted Answer

A) the new strand will contain the incorrect base if a mismatch occurs. 
B) older DNA is more likely to contain errors. 
C) older DNA contains methyl groups at specific sequences 
D) newer DNA contains methyl groups at specific sequences 
E) the DNA polymerase is attached to the new strand 
A) the new strand will contain the incorrect base if a mismatch occurs. 
B) older DNA is more likely to contain errors. 
C) older DNA contains methyl groups at specific sequences 
D) newer DNA contains methyl groups at specific sequences 
E) the DNA polymerase is attached to the new strand

Question 5

The Ames test for mutagenicity is useful to identify potential carcinogens because

Accepted Answer

A) bacteria do not get cancer they can survive lethal carcinogens. 
B) mutagens that affect bacterial DNA are likely to cause human mutation. 
C) bacteria thrive on substances that could cause cancer in humans. 
D) the same genes that cause cancer in humans can be mutated in bacteria. 
E) liver enzymes alter the bacteria so they will behave like mammal cells. 
A) bacteria do not get cancer they can survive lethal carcinogens. 
B) mutagens that affect bacterial DNA are likely to cause human mutation. 
C) bacteria thrive on substances that could cause cancer in humans. 
D) the same genes that cause cancer in humans can be mutated in bacteria. 
E) liver enzymes alter the bacteria so they will behave like mammal cells.

Question 6

The consequence to a bacterial cell of a mutation that inactivated the enzyme that methylates the A of the sequence GATC in newly made DNA would be

Accepted Answer

A) failure to carry out replication 
B) failure to correct thymine dimers. 
C) failure to distinguish old and new DNA during mismatch repair. 
D) inactivation of certain metabolic genes. 
E) decrease in the mutation rate 
A) failure to carry out replication 
B) failure to correct thymine dimers. 
C) failure to distinguish old and new DNA during mismatch repair. 
D) inactivation of certain metabolic genes. 
E) decrease in the mutation rate

Question 7

Choose the condition below that does not involve a defect in an enzyme pathway.

Accepted Answer

A) Alkaptonuria 
B) albinism 
C) sickle cell anemia 
D) Phenylketonuria (PKU) 
A) Alkaptonuria 
B) albinism 
C) sickle cell anemia 
D) Phenylketonuria (PKU)

Question 8

Assume that a researcher is studying coat color in voles.Three strains of white vole have been isolated: milky, blanc, and weiss.White is a recessive trait in each strain.Homozygous white voles are obtained for each strain.Consider the following crosses: milky * blanc = all white progeny
Milky * weiss = all brown (wild-type vole color)
Blanc * weiss = all brown (wild-type vole color)
The conclusion most consistent with these results is

Accepted Answer

A) all three strains have mutations in the same gene. 
B) all three strains have mutations in different genes. 
C) milky and blanc have mutations on the same gene, weiss has a mutation in a different gene. 
D) milky and weiss have mutations on the same gene, blanc has a mutation in a different gene. 
E) weiss and blanc have mutations on the same gene, milky has a mutation in a different gene. 
A) all three strains have mutations in the same gene. 
B) all three strains have mutations in different genes. 
C) milky and blanc have mutations on the same gene, weiss has a mutation in a different gene. 
D) milky and weiss have mutations on the same gene, blanc has a mutation in a different gene. 
E) weiss and blanc have mutations on the same gene, milky has a mutation in a different gene.

Question 9

Indicate which of the following is least important in doing a complementation test with coinfection of phage T4.

Accepted Answer

A) ensuring that sufficient phage of both strains are present 
B) recovering phage from the plaques after growth and lysis 
C) counting the plaques that are produced on 
D) control using both mutations in cis configuration and a wild type 
E) coli K($\lambda$) 
A) ensuring that sufficient phage of both strains are present 
B) recovering phage from the plaques after growth and lysis 
C) counting the plaques that are produced on 
D) control using both mutations in cis configuration and a wild type 
E) coli K($\lambda$)

Question 10

Consider the pathway for the synthesis of the amino acid arginine in Neurospora:   Mutant strains of Neurospora are grown in minimal media supplements as follows.The strains may carry more than one mutation.Growth is shown by (+) and no growth is shown by (o).   Strain a accumulates citrulline, strain b does not.Indicate the statement that is most correct regarding these two strains.

Accepted Answer

A) Strain a has a mutation in ARG-E only. 
B) Strain b has only one mutation. 
C) Strain a has mutations in ARG-F and ARG-H. 
D) Strain a has mutations in ARG-E, ARG-F and ARG-H. 
E) Strain a has a mutation in ARG-H only. 
A) Strain a has a mutation in ARG-E only. 
B) Strain b has only one mutation. 
C) Strain a has mutations in ARG-F and ARG-H. 
D) Strain a has mutations in ARG-E, ARG-F and ARG-H. 
E) Strain a has a mutation in ARG-H only.

Question 11

In the Ames test for mutagenicity

Accepted Answer

A) auxotrophic bacteria are converted to prototrophs that survive. 
B) prototrophic bacteria are converted to auxotrophs that survive. 
C) cells are treated with mutagen and only those with no mutations survive 
D) cells are treated with excess amino acids, killing cells that carry mutations. 
E) rat liver enzymes protect cells from mutation 
A) auxotrophic bacteria are converted to prototrophs that survive. 
B) prototrophic bacteria are converted to auxotrophs that survive. 
C) cells are treated with mutagen and only those with no mutations survive 
D) cells are treated with excess amino acids, killing cells that carry mutations. 
E) rat liver enzymes protect cells from mutation

Question 12

Thymine dimers are caused by

Accepted Answer

A) X-rays. 
B) free radicals such as oxygen. 
C) EMS or NSG. 
D) depurination. 
E) UV light. 
A) X-rays. 
B) free radicals such as oxygen. 
C) EMS or NSG. 
D) depurination. 
E) UV light.

Question 13

Consider the pathway for the synthesis of the amino acid arginine in Neurospora:   Mutant strains of Neurospora are grown in minimal media supplements as follows.Strains may carry more than one mutation.Growth is shown by (+) and no growth is shown by (o).   Indicate the most accurate statement regarding strain A.

Accepted Answer

A)  There is a mutation in ARG-H, if citrulline accumulates, ARG-F is also defective. 
B)  There is a mutation in ARG-H, if ornithine accumulates, ARG-F is also defective. 
C)  There is a mutation in ARG-H, if argininosuccinate accumulates, ARG-F is also defective. 
D)  There is a mutation in ARG-H, if citrulline accumulates, ARG-E is also defective. 
E)  There is a mutation in ARG-E, if citrulline accumulates, ARG-F is also defective. 
A)  There is a mutation in ARG-H, if citrulline accumulates, ARG-F is also defective. 
B)  There is a mutation in ARG-H, if ornithine accumulates, ARG-F is also defective. 
C)  There is a mutation in ARG-H, if argininosuccinate accumulates, ARG-F is also defective. 
D)  There is a mutation in ARG-H, if citrulline accumulates, ARG-E is also defective. 
E)  There is a mutation in ARG-E, if citrulline accumulates, ARG-F is also defective.

Question 14

Shown below are the deletion maps of a series of rII- mutations.The deleted region is indicated as (......) and the intact region as ______.Note that strain 5 carries two different deletions.1 ___________(...........)_______________ 2 _________________(...........)_________
3 ()....................)_____________________
4 ________________________(................)
5 _____(..........)________________(.........)
A series of point mutations A E is used in a coinfection experiment.Shown below are the results of those coinfections.Ability to produce wild-type progeny phage is indicated by (+), and (o) indicates no wild-type progeny.     Indicate the order that is most consistent with these data.

Accepted Answer

A) CADBE 
B) DEBAC 
C) BADCE 
D) ABDEC 
E) CEADB 
A) CADBE 
B) DEBAC 
C) BADCE 
D) ABDEC 
E) CEADB

Question 15

Assume eight different strains of fly have been isolated, each shows a recessive white eye trait.Crosses are performed as follows (w) indicates white-eyed progeny, (R) indicates wild-type red eyes.   Based on these crosses, how many different genes are present and what strains have mutations in the same gene as does strain A?

Accepted Answer

A) 2, B, E, and H 
B) 3, B, and C 
C) 3, B, C, and H 
D) 3, B, E, and H 
E) 4, B, and H 
A) 2, B, E, and H 
B) 3, B, and C 
C) 3, B, C, and H 
D) 3, B, E, and H 
E) 4, B, and H

Question 16

In the human genetic disorder Alkaptonuria, urine turns black because of the presence of homogentisic acid in individuals with the trait.This is due to

Accepted Answer

A) the presence of large amounts of homogentisic acid in the diet. 
B) failure of individuals with Alkaptonuria to manufacture enzymes involved in the synthesis of homogentisic acid. 
C) failure of wild-type individuals to manufacture enzymes involved in the synthesis of homogentisic acid. 
D) failure of the kidneys to remove homogentisic acid from the urine. 
E) failure of individuals with Alkaptonuria to manufacture enzymes involved in the breakdown of homogentisic acid. 
A) the presence of large amounts of homogentisic acid in the diet. 
B) failure of individuals with Alkaptonuria to manufacture enzymes involved in the synthesis of homogentisic acid. 
C) failure of wild-type individuals to manufacture enzymes involved in the synthesis of homogentisic acid. 
D) failure of the kidneys to remove homogentisic acid from the urine. 
E) failure of individuals with Alkaptonuria to manufacture enzymes involved in the breakdown of homogentisic acid.

Question 17

Indicate the correct order for one round of infection by bacteriophage T4.1) Lysis of host cell.2) Phage proteins and DNA synthesized, host DNA degraded.3) Assembly of phage within host cell.4) Phage body enters host cell.5) Phage injects DNA into host cell.

Accepted Answer

A) 4, 2, 3, 1 
B) 1, 2, 3, 4, 5 
C) 5, 1, 2, 3, 
D) 5, 2, 3, 1 
E) 4, 5, 3, 1 
A) 4, 2, 3, 1 
B) 1, 2, 3, 4, 5 
C) 5, 1, 2, 3, 
D) 5, 2, 3, 1 
E) 4, 5, 3, 1

Question 18

The duplication of the triplet sequence CGG resulting in elongation or breakage of the X chromosome is termed

Accepted Answer

A) Barr-eyed. 
B) Huntington's disease. 
C) unequal crossing over 
D) Fragile X syndrome. 
E) Rhys syndrome 
A) Barr-eyed. 
B) Huntington's disease. 
C) unequal crossing over 
D) Fragile X syndrome. 
E) Rhys syndrome

Question 19

Choose the statement below that is not true regarding sickle cell anemia.

Accepted Answer

A) Individuals who are heterozygous for the sickle cell allele cannot make hemoglobin. 
B) The sickle cell hemoglobin molecule contains an amino acid substitution. 
C) The hemoglobin molecules of an individual with sickle cell anemia clump together. 
D) The red blood cells of an individual with sickle cell anemia distort and elongate. 
A) Individuals who are heterozygous for the sickle cell allele cannot make hemoglobin. 
B) The sickle cell hemoglobin molecule contains an amino acid substitution. 
C) The hemoglobin molecules of an individual with sickle cell anemia clump together. 
D) The red blood cells of an individual with sickle cell anemia distort and elongate.

Question 20

If a man shows the premutation allele for Fragile X syndrome, what is the probability that he will pass it on to his son?

Accepted Answer

A) 100% 
B) 75% 
C) 50% 
D) 25% 
E) 0% 
A) 100% 
B) 75% 
C) 50% 
D) 25% 
E) 0%

The term mutation refers to

Though sickle cell anemia is frequently lethal for individuals who are homozygous for the sickle cell allele, natural selection seems to have maintained that allele in certain geographic locations.A likely explanation for this observation is

The bacterial repair system that corrects mismatched bases after polymerization is able to discriminate between the old and newly made DNA strands because

The Ames test for mutagenicity is useful to identify potential carcinogens because

The consequence to a bacterial cell of a mutation that inactivated the enzyme that methylates the A of the sequence GATC in newly made DNA would be

Choose the condition below that does not involve a defect in an enzyme pathway.

Indicate which of the following is least important in doing a complementation test with coinfection of phage T4.

In the Ames test for mutagenicity

Thymine dimers are caused by

In the human genetic disorder Alkaptonuria, urine turns black because of the presence of homogentisic acid in individuals with the trait.This is due to

Indicate the correct order for one round of infection by bacteriophage T4.1) Lysis of host cell.2) Phage proteins and DNA synthesized, host DNA degraded.3) Assembly of phage within host cell.4) Phage body enters host cell.5) Phage injects DNA into host cell.

The duplication of the triplet sequence CGG resulting in elongation or breakage of the X chromosome is termed

Choose the statement below that is not true regarding sickle cell anemia.

If a man shows the premutation allele for Fragile X syndrome, what is the probability that he will pass it on to his son?

Genetics: The Study of Biological Information

Mendels Principles of Heredity

Extensions to Mendels Laws

The Chromosome Theory of Inheritance

Linkage, Recombination, and the Mapping of Genes on Chromosomes

DNA Structure, Replication, and Recombination

Gene Expression: The Flow of Information From DNA to RNA to Protein

Digital Analysis of Genomes

Analyzing Genomic Information

The Eukaryotic Chromosome

Chromosomal Rearrangements and Changes in Chromosome Number

Bacterial Genetics

Organellar Inheritance

Gene Regulation in Prokaryotes

Gene Regulation in Eukaryotes

Manipulating the Genomes of Eukaryotes

The Genetic Analysis of Development

The Genetics of Cancer

Variation and Selection in Populations

Genetics of Complex Traits

Filters

Exam 7: Anatomy and Function of a Gene: Dissection Through Mutation

The term mutation refers to

Though sickle cell anemia is frequently lethal for individuals who are homozygous for the sickle cell allele, natural selection seems to have maintained that allele in certain geographic locations.A likely explanation for this observation is

The bacterial repair system that corrects mismatched bases after polymerization is able to discriminate between the old and newly made DNA strands because

The Ames test for mutagenicity is useful to identify potential carcinogens because

The consequence to a bacterial cell of a mutation that inactivated the enzyme that methylates the A of the sequence GATC in newly made DNA would be

Choose the condition below that does not involve a defect in an enzyme pathway.

Indicate which of the following is least important in doing a complementation test with coinfection of phage T4.

In the Ames test for mutagenicity

Thymine dimers are caused by

In the human genetic disorder Alkaptonuria, urine turns black because of the presence of homogentisic acid in individuals with the trait.This is due to

Indicate the correct order for one round of infection by bacteriophage T4.1) Lysis of host cell.2) Phage proteins and DNA synthesized, host DNA degraded.3) Assembly of phage within host cell.4) Phage body enters host cell.5) Phage injects DNA into host cell.

The duplication of the triplet sequence CGG resulting in elongation or breakage of the X chromosome is termed

Choose the statement below that is not true regarding sickle cell anemia.

If a man shows the premutation allele for Fragile X syndrome, what is the probability that he will pass it on to his son?

Genetics: The Study of Biological Information

Mendels Principles of Heredity

Extensions to Mendels Laws

The Chromosome Theory of Inheritance

Linkage, Recombination, and the Mapping of Genes on Chromosomes

DNA Structure, Replication, and Recombination

Gene Expression: The Flow of Information From DNA to RNA to Protein

Digital Analysis of Genomes

Analyzing Genomic Information

The Eukaryotic Chromosome

Chromosomal Rearrangements and Changes in Chromosome Number

Bacterial Genetics

Organellar Inheritance

Gene Regulation in Prokaryotes

Gene Regulation in Eukaryotes

Manipulating the Genomes of Eukaryotes

The Genetic Analysis of Development

The Genetics of Cancer

Variation and Selection in Populations

Genetics of Complex Traits

Filters